Description
Both sexes reach about 5 mm in body length. Females and immatures of both sexes are brown but have color patterns by which they can be distinguished from related species.Behavior
Courtship
The red, blue and black colored males have flap-like extensions of theVibrations
An important part of the male peacock spider’s courtship is the vibrations that accompany the fan dance. The exact mechanism of how these vibrations are produced is not known, but it is known that they are produced almost solely from rapid movements in their abdomen. There are three kinds of vibrations: rumble-rumps, crunch rolls, and grind-revs. Rumble-rumps are continuously emitted during the courtship, and can even start before the male sees the female. The name comes from the two distinct sounds, the rumble and the rump. The crunch rolls and grind-revs are observed right before the pre-mount display. Males who put forth more effort in both the visual display and the vibratory signaling had a higher success in mating. Having a higher measured effort meant putting in more time engaged in the visual display or vibrating with more vigor. Both of these are postulated to indicate a healthier and more fit male. However, visual displays are more strongly linked to mating success than vibratory signaling.Female choice
For females who do choose to mate with the male, copulation time is also positively correlated to visual displays and vibratory signaling. Other aspects that are important include persistence, staying within proximity of the female and maintaining constant visual contact with her. If the female is interested she will occasionally respond to the approaching male by signaling with her third pair of legs. Her legs will be stretched out as they move, often times one leg more engaged than the other. In ''M. volans'', they found that the females are only likely to mate once.Female aggression
If the male continues his dance when the female is not interested, she attempts to attack, kill, and feed on him; she may also do this after mating (Copulation and pre-mount display
During the courtship display the male will slowly approach the female, as he lowers his carapace almost to the ground until they are about one body length apart. If the female does not flee then he will commence the pre-mount display. The pre-mount display is a highly conserved behavior; the ''Maratus volans'' will follow a specific sequence: the third legs are rotated to the front over the first and second legs, while he retracts his colorful fan flaps. The third legs are lowered and spread apart as they tremor. The first legs will be held erect in front of the body almost touching the female. After this, the male will advance towards the female. Copulation can last a duration of several minutes to several hours. Throughout the whole courtship event, the male performs pedipalp flickers either alone or along with the other courtship displays. However, the pedipalp flicker may not be specific to courtship because it is also observed in other contexts like eating.Pheromones
Contact pheromones, which are often released onto the silk drag-lines, can be detected by chemoreceptors on both the legs and palps. These pheromones, which are released by the abdomen of the female spider, can trigger male courtship even in the absence of visual cues. Pheromones given off by the female may be an indication of if they are already mated, and can hint to any other males whether or not to pursue courtship.Sexual selection
''M. volans'' use their colorfulHunting and diet
Peacock spiders are diurnal cursorial hunters feeding primarily on insects and other spiders. The evolution of an acute visual system in salticids almost certainly originated as an adaptation for stalking prey. However, this development also facilitated a wandering lifestyle different from that of their sit-and-wait ancestors, enabling jumping spiders to roam and encounter many environments. Keen eyesight has probably been useful for peacock spiders in navigating, inhabiting and exploiting new types of habitats, and undoubtedly set the stage for the evolution of complex visual signals. Like other jumping spiders, they do not rely on webs to catch prey. They use their keen eyesight to stalk their prey and eventually chase and leap on their target to deliver a fatal bite. They have been observed to jump up to 40 times higher than their body length.Reproduction and lifecycle
Activity
''M. volans'' are typically most active during the spring (Austral Spring), which is their breeding season. The mature males appear from August to December, while the females appear a bit later and survive longer. In December, the females will stay hidden in order to lay their eggs and guard them from predators.Life cycle
Immature female peacock spiders resemble the adults, except their pedipalps are colorless. The immature male peacock spiders lack an opisthosomal fan, a prominent white marginal band of the carapace, as well as specialization of the third legs. The males do not generate their colorful colors until sexual maturity. Their lifespan is reported to be about one year.Eggs
In December, the females are observed to create nests underground where they will lay eggs. ''M. volans'' females have been observed to lay between 6 to 15 eggs per clutch. Some ''M. volans'' were observed to have several consecutive broods. Males hatch in August and can survive through December, while females hatch a bit later and tend to survive longer than males.Distribution and habitat
Distribution
''M. volans'' is confined to specific parts of Australia (Queensland, New South Wales, Australian Capital Territory, Western Australia and Tasmania).Platnick 2009 They have a very wide distribution and occupy many different types of environments, unlike other species of ''Maratus'' that occupy only a niche habitat, like the ''M. Sarahae.''Habitat
The majority of Peacock spiders are ground dwelling and found on leaf litter or dry twigs. The females are thought to mimic leaf scars on the dry twigs; however, they can be found in a wide variety of habitats such as sand dunes to grasslands.Physiology
Eyesight
Peacock spiders each have eight eyes that are equipped with a telephoto lens, tiered retina, and UV-sensitive photoreceptor. They have reached the physical limit of optical resolution given their size. This special visual system allows them to see the full visible spectrum as well as in the UV-range. They have a set of primary eyes that provide acute vision and secondary eyes that aid them to detect motion. Their superb eyesight is useful in pursuing prey.Scales
The male abdomen contains scales that produce its well known colorful display. Some male peacock spiders are able to change their scales from red to green to violet with slight movements, using their specialized abdominal scales that contain three dimensional reflective diffraction grating structures. They can reflect light in both the visible and the ultraviolet range.Name
The English arachnologistReferences
Sources
* Ed NieuwenhuysExternal links